Horun (excavation) method

1. Compact vertical shaft
2. Acceleration of vertical shaft driving
3. Greater economy at greater depths
4. Great safety at great depths

Continuous vertical-to-horizontal shield machine
(vertical-to-horizontal shield machine)

 Excavation is carried out by a single shield machine continuously from the ground surface first in the vertical shaft then in the adit. This method performs the functions of caissons or diaphragm walls required by conventional methods for driving a vertical shaft, so it contributes to easier construction, shorter construction period and reduced cost.

Perpendicular shield machine
(horizontal-to-horizontal shield machine)

 A single shield machine continuously excavates a tunnel, curving horizontally at a right angle. The machine is highly effective in underground spaces below congested intersections or occupied by buried structures where no vertical shaft can be driven for turning the shield machine.

Construction of the Bandai ~ Hannan trunk sewer
(Vertical-to-horizontal shield machine)
Shield diameters
Vertical diameter : 5.90 m
Horizontal diameter: 4.20 m
Type: Slurry shield (Vertical)
Earth pressure balanced shield (Horizontal )

Construction of the Shimoji sewer
(Horizontal-to-horizontal shield machine)
Shield diameters
Main shield diameter: 3.93 m
Sub-shield diameter : 2.68 m
Type: Slurry shield
  Kurun (rotation) method

1. Cutter bits can be replaced any number of times at any time.
2. The number of days required for construction can be reduced substantially.
3. Great safety and reliability can be obtained.
4. Extraordinarily great economic benefits are

Long-distance shield machine

 The machine is effective in excavating long distances continuously. Cutter bits can be replaced simply by rotating the cutter head. The method has eliminated ground improvement and other measures required by conventional methods and ensures great construction efficiency and safety.

Construction of the Nippa Suehiro main sewer
(Long-distance shield machine)
Shield diameter: 9.45 m
Type: Slurry shield
Length: 4435 m

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